JP6195793B2 - Automatic syringe - Google Patents

Description

  The present invention relates to a compression coupling means for an auto-injector configured to attach an auto-injector front device to an auto-injector rear device.

  Giving an injection is a risky and challenging process for both users and healthcare professionals, both mentally and physically.

  Syringes (ie devices that can deliver medication from a pharmaceutical container) are usually divided into two categories: manual devices and automatic syringes.

  In manual devices, the user must supply mechanical energy to move the fluid through the needle. This is usually done by some form of button / plunger that the user must hold down during the injection. This approach has many disadvantages to the user. When the user stops pressing the button / plunger, the injection stops. This means that if the device is not used properly (ie, the plunger is not fully pushed to its end position), the user may deliver an underdose. Note input can be too strong for the user, especially if the patient is elderly or clumsy.

  Button / plunger extension may be too large. Therefore, it may be inconvenient for the user to reach for the fully extended button. Combining note input and button extension can cause hand tremors, which in turn increases discomfort when the inserted needle moves.

  The auto-injector device aims to provide easier self-administration of injection therapy for the patient. Currently, therapies performed by self-administration injection include drugs such as diabetes drugs (insulin and newer GLP-1 class drugs), migraine, hormone therapy, anticoagulants and the like.

  An automatic injector is a device that completely or partially replaces the work associated with parenteral drug delivery from a standard syringe. Such operations may include removal of the protective syringe cap, insertion of the needle into the patient's skin, drug injection, needle removal, needle shielding, and prevention of device reuse. This overcomes many of the disadvantages of manual devices. Order entry / button extension, hand tremors, and the possibility of delivering insufficient dose is reduced. Activation can be accomplished by a number of means, for example, the action of a trigger button or needle reaching the injection depth. In some devices, the energy to deliver the fluid is provided by a spring.

  Patent Document 1 discloses an automatic injection device that automatically injects a pre-measured amount of fluid medicine when a tension spring is released. When released, the tension spring moves the ampoule and injection needle from the retracted position to the deployed position. Thereafter, the tension spring pushes the piston forward into the ampoule, thereby releasing the contents of the ampoule. After the fluid medicine is injected, the twist stored in the tension spring is released and the injection needle is automatically retracted to the original retracted position.

US Patent Application Publication No. 2002 / 0095120A1

  An object of the present invention is to provide a front device of an auto-injector configured to receive a syringe having an injection needle and an outer cylinder containing a dose of drug, for advancing the syringe to insert the needle and to deliver the drug To provide an improved means for releasably connecting to a rear device with drive means.

  This object is achieved by the compression coupling means according to claim 1.

  Preferred embodiments of the invention are indicated in the dependent claims.

  In the context of this specification, the term proximal refers to the direction toward the patient during injection and the term distal refers to the opposite direction away from the patient. The terms “clockwise” and “counterclockwise” in the context of the present specification indicate the direction of rotation with the auto-injector with its distal end facing the viewer.

According to the present invention, the front device and the rear device of the automatic injector can be releasably connected by the compression connection means,
An annular mounting sleeve that is axially displaceable parallel to the longitudinal axis between a locked position and an unlocked position;
-A mounting sleeve spring biasing the mounting sleeve towards the locked position;
-Comprising at least one latch arm coupled to either the front device or the rear device.

  The latch arm is radially deflectable, the mounting sleeve in the locked position is arranged to prevent radial deflection of the latch arm, and the mounting sleeve in the unlocked position is Enables radial deflection so that the latch arm deflects when the front device is assembled to or disassembled from the rear device and latches to the other of the front or rear device or latches from the other To be released.

  The compression coupling means can be applied with a front device of an automatic syringe for administering a dose of liquid medicament. The front device is configured to receive a prefilled syringe having an injection needle and a barrel containing a dose of drug, and includes a tubular outer sleeve and compression coupling means.

  A syringe holder configured to receive a filled syringe can be slidably disposed with respect to the outer sleeve. The syringe retainer is arranged to translate between a first position where the needle is hidden within the outer sleeve and a second position where the needle projects proximally from the outer sleeve. The syringe holder can comprise at least one flexible arm arranged to hook onto the outer sleeve and releasably hold the syringe holder in the first position.

  A needle shroud configured to be placed on the patient's skin may be slidably disposed relative to the outer sleeve. The needle shroud is arranged to translate between an advanced position and a retracted position. The needle shroud includes an extension arm arranged to engage a release ramp on the syringe holder to unlatching the syringe holder from the outer sleeve when the needle shroud is in the retracted position. In particular, the needle shroud can be arranged to axially translate to a retracted position by pressing against the skin. By communicating the axial displacement of the needle shroud to the posterior device of the auto-injector, the extension arm can be configured to indicate to the posterior device whether the auto-injector is properly positioned on the patient's skin. The posterior device may have means to prevent actuation of the injection mechanism when the needle shield is not in the retracted position and is not in contact with the patient's skin. Thus, premature actuation or inadvertent actuation of the injection mechanism that wastes medication and / or compromises safety is avoided.

The front device can be part of an auto-injector for administering liquid drug doses,
-Housing,
A plunger connected or configured to engage a stopper that provides a fluid tight seal against the distal end of the syringe barrel;
A reusable rear device with a motor for displacing the plunger connected to the stopper;

  The front device can be attached to the rear device via compression coupling means.

  A tubular cover may be coupled to the needle cap that covers the syringe needle, and the tubular cover is positioned to facilitate removal of the needle cap when the syringe is held in the front device.

  A prefilled syringe is loaded into the front device before an injection is made. The front device then grips the mounting sleeve and axially displaces the mounting sleeve relative to the outer sleeve against the biasing force of the mounting sleeve spring in the proximal direction to the unlocked position, thereby causing the front device to compress the coupling means. Attached to the rear device. With the mounting sleeve in the unlocked position, the latch arm can be deflected radially outward by pushing the tubular end of the housing against the slope of the latch arm during insertion or removal. This allows the tubular end of the housing to be inserted and / or withdrawn from the open distal end of the front device when the mounting sleeve is in the unlocked position. When the tubular end is fully inserted, the latch arm can be loosened and latched into each opening in the tubular end of the housing. Because the user can release the mounting sleeve, the mounting sleeve spring can translate the mounting sleeve into the unlocked position. When the tubular end of the housing is inserted into the open distal end of the front device, the plunger is inserted into the syringe barrel to engage the syringe stopper. The latch arm latches at the proximal end of the housing to attach the front device to the rear device. This allows the automatic injector to be assembled particularly simply and intuitively before making an injection.

  The back and front devices of the auto-injector are designed to be used for multiple injections. The only single use element is a prefilled syringe that is inserted into the front device prior to assembly of the auto-injector. This reduces manufacturing costs and minimizes waste.

  In accordance with yet another possible embodiment of the present invention, axial displacement detection of a needle shroud that is slidably disposed with respect to a support sleeve and configured to rest on the skin of a patient receiving an injection. Possible interlock switches can be placed in the rear device. Thus, the interlock switch detects whether the needle shroud is in contact with the patient's skin and is preferably part of a mechanism that prevents operation of the rear device motor. The motor of the rear device can be an electric motor, a spring drive motor, a pneumatic motor, or another drive means.

  According to yet another possible embodiment of the invention, the posterior device comprises a sensor unit for detecting actual parameters of the injection and a memory unit for storing user related data and / or specification parameters. And means for providing visual, auditory and / or tactile feedback to the user of the auto-injector. Since stored user-related data can be used for compliance monitoring, it can be used to monitor the frequency of injections performed by the patient. In particular, if the patient is on medication, the appropriate dose and / or frequency of administration can be managed.

  The sensor unit can detect actual parameters such as the type of drug or drug contained in the prefilled syringe, especially by wireless automatic identification (RFID) or barcode reading. This enables, among other things, automatic configuration of the automatic injector for drug properties. For example, the puncture depth of the injection needle can be automatically adjusted to the depth required by the drug. Furthermore, a set of device specification parameters can be stored in the memory unit. Specification parameters stored in the memory unit can be compared to actual parameters determined by the sensor unit during use of the auto-injector. For example, the current measured during the needle insertion process is characterized by the force required to insert the injection needle into the skin. If the measured current is out of specification, the posterior device detects misuse of the automatic syringe and stops the injection. Another possible application involves comparing the initial position of the stopper with the corresponding specification parameters at the start of the injection. If the stopper position is out of specification, the rear device detects that a used empty syringe is loaded into the front device and disables the injection mechanism to prevent damage. The automatic injector cannot operate when the syringe is not inserted into the syringe holder.

  The visual means of the posterior device can include, in particular, a display, preferably a liquid crystal display (LCD), showing drug properties such as injection progress, injection completion, historical user data and / or expiration date. The display can display a message reminding the patient to administer the medication, specification parameters, operating modes, and / or the type of medication contained in the prefilled syringe. In addition or alternatively, the posterior device may comprise suitable means for providing audio and / or tactile feedback to the patient and / or the user of the auto-injector.

  According to yet another possible embodiment of the invention, the rear device further comprises an encoder sensor capable of determining the position of the plunger. Plunger position detection can be used to control the translational speed of the plunger. In particular, the translational speed of the plunger can be tailored to various stages of drug delivery including needle insertion, drug release, and needle retraction stages. In particular, the encoder sensor can be configured as a rotary or linear encoder that can detect the position of the plunger and convert the detected position into a corresponding digital or analog signal.

  The auto-injector preferably delivers one of analgesics, anticoagulants, insulin, insulin derivatives, heparin, lobenox, vaccines, growth hormones, peptide hormones, proteins, antibodies, and glycoconjugates, among others Can be used for subcutaneous or intramuscular injection.

  Further scope of applicability of the present invention will become apparent from the detailed description provided hereinafter. However, the detailed description and specific examples, while indicating the preferred embodiment of the invention, are exemplary only. This is because various changes and modifications within the spirit and scope of the present invention will become apparent to those skilled in the art from this detailed description.

  The present invention will become more fully understood from the detailed description set forth below and the accompanying drawings, which are given by way of illustration only and are not intended as a limitation of the present invention.

FIG. 3 is a cross-sectional view of a reusable front device before a filled syringe is loaded into the front device. FIG. 3 is a cross-sectional view of a reusable front device before a filled syringe is loaded into the front device. It is a perspective view of a syringe holder. It is a perspective view of a syringe holder. FIG. 6 is a cross-sectional view of the front device during syringe assembly. FIG. 6 is a cross-sectional view of the front device during syringe assembly. FIG. 4 shows a front device of the present invention connected to a rear device. FIG. 4 shows a front device of the present invention connected to a rear device. FIG. 7 is a cross-sectional view of the front device during injection. FIG. 7 is a cross-sectional view of the front device during injection. FIG. 2 is a perspective view of an assembled auto-injector with a rear device 3 and a front device. FIG. 2 is a cross-sectional view of an assembled auto-injector with a rear device 3 and a front device.

  Corresponding parts are designated by the same reference numerals in all figures.

  1A and 1B are cross-sectional views of a reusable front device 1.

  The automatic injector A includes a substantially cylindrical front device 1, a reusable rear device 3, and a syringe 2 that can be inserted into the front device 1. The front device 1 can be attached to the reusable rear device 3 via compression coupling means. The rear device 3 provides the automatic injector A with the various functions described above. In particular, the rear device 3 includes the components described above.

  1A and 1B show the front device 1 before it is loaded with a syringe 2 containing a dose of liquid medicament.

  The rear device 3 (shown in FIGS. 6A and 6B) includes a driving means such as the electric motor 3.5 of the automatic injector A, and by operating this driving means, the filled syringe 2 is placed in the front device 1. Can be translated parallel to the axis X of the substantially cylindrical front device 1 to release the drug contained in the pre-filled syringe 2.

  The front device 1 includes a tubular outer sleeve 1.1, a syringe holder 1.3 configured to receive a syringe 2, an annular mounting sleeve 1.11 and a substantially cylindrical needle shroud 1.4. Prepare. Needle shroud 1.4 and syringe holder 1.3 are slidably arranged relative to outer sleeve 1.1.

  An annular projection 1.1.1 is formed on the inner surface of the outer sleeve 1.1 and projects radially inward. A transmission spring 1.5 hits the needle shroud 1.4 in the proximal direction P and abuts the annular projection 1.1.1 in the distal direction D to bias the needle shroud 1.4 in the proximal direction P Let The needle shroud 1.4 is located in the advanced position PA and projects in the proximal direction P from the outer sleeve 1.1 of the front device 1.

  At least one, but preferably two or more flexible arms 1.3.2 are formed on the side wall of the syringe holder 1.3. The flexible arms 1.3.2 are arranged on both sides of the syringe holder 1.3 and latch to the outer sleeve 1.1 so that the syringe when the filled syringe 2 is loaded into the syringe holder 1.3 Prevent axial translation of holder 1.3. The flexible arm 1.3.2 is formed on the needle shroud 1.4 and can be engaged by an extension release arm 1.4.2 projecting in the distal direction D from the needle shroud 1.4. 3.3. The extension arm 1.4.2, which engages the release ramp 1.3.3, unlatches the flexible arm 1.3.2, releases the syringe holder 1.3, and the syringe holder 1. 3 is axially displaceable in the proximal direction P with respect to the outer sleeve 1.1.

  A longitudinal first recess 1.1.3 is formed on the inner surface of the distal part of the outer sleeve 1.1 parallel to the longitudinal axis X. The first recess 1.1.3 accommodates a first fastener 1.3.4 formed on the outer surface of the syringe holder 1.3. The first fastener 1.3.4 is held in the first recess 1.1.3 so as to limit the axial displacement in the distal direction D of the syringe holder 1.3 relative to the outer sleeve 1.1. Is done.

  The return spring 1.8 abuts in the proximal direction on the annular projection 1.1.1 and abuts in the distal direction D on the circumferential abutment surface 1.3.5 of the syringe holder 1.3. The return spring 1.8 biases the syringe holder 1.3 in the distal direction D with respect to the outer sleeve 1.1.

  A radially projecting annular flange 1.4.3 is formed at the proximal end of the needle shroud 1.4. The annular flange 1.4.3 is configured to rest on the patient's skin during injection. A second fastener 1.4.4 projects radially outward from the outer surface of the needle shroud 1.4 and enters a second recess 1.1.4 formed in the inner surface of the outer sleeve 1.1. The second fastener 1.4.4 runs along the second recess 1.1.4 and limits the maximum axial displacement of the needle shroud 1.4 relative to the outer sleeve 1.1.

  An annular mounting sleeve 1.11 surrounds the distal portion of the outer sleeve 1.1 and is slidably arranged with respect to the outer sleeve 1.1. A mounting sleeve spring 1.7.1 arranged as a compression spring biases the mounting sleeve 1.11 against the outer sleeve 1.1 in the distal direction D towards the locking position L. In the locked position L, the mounting sleeve 1.11 provides a counter bearing for the latch arm 1.1.2 shown in FIG. 1B.

  At least one, but preferably two or more latch arms 1.1.2 are formed on either side of the distal portion of the outer sleeve 1.1, the latch arms 1.1.2 being The front device 1 can be attached to the housing 3.1 by latching in the housing 3.1 of the rear device 3. The mounting sleeve 1.11 abuts the latch arm 1.1.2 radially inward to prevent the latch arm 1.1.2 from deflecting outward. The mounting sleeve 1.11, the mounting sleeve spring 1.7.1, and the latch arm 1.1.2 provide a compression coupling means for mounting the front device 1 to the rear device 3 of the auto-injector A.

  As best seen in FIG. 1B, a plurality of radially inwardly holding retaining projections 1.3.6 are configured to frictionally engage the outer cylinder 2.3 of the syringe 2. Formed on the inner surface.

  2A and 2B show the syringe holder 1.3 in different perspective views. The syringe holder 1.3 is a flexible arm having a first fastener 1.3.4, an abutment surface 1.3.5, a holding projection 1.3.6, and a release bevel 1.3.3. Characterized by 1.3.2. A plurality of friction ribs 1.3.7 are formed at the distal end of the syringe holder 1.3. The friction rib 1.3.7 protrudes radially inward and is configured to frictionally engage the outer cylinder collar 2.3.1 of the syringe 2 to attach the syringe 2 to the syringe holder 1.3 (see FIG. (Shown in 3B).

  3A and 3B are two different cross-sectional views of the front device 1. The filled syringe 2 is inserted into the syringe holder 1.3 held in the retracted first position I, and the injection needle 2.2 attached to the proximal tip of the filled syringe 2 is connected to the front device. 1 is held.

  The syringe 2 includes a stopper 3.3 that seals the outer cylinder 2.3 in a liquid-tight manner and can be connected to the plunger 3.2 of the rear device 3. The stopper 3.3 can be displaced in the proximal direction P and the dose of the drug contained in the outer cylinder 2.3 can be released through the injection needle 2.2 of the filled syringe 2.

  The injection needle 2.2 is covered by a needle cap 2.1. Before or after the syringe 2 is inserted into the front device 1, an elongate tubular cover 2.4 is attached to the proximal end of the syringe 2 and is fitted and held in the needle cap 2.1 by a snap (see FIG. 3). The The tubular cover 2.4 projects from the proximal end of the front device 1 when the syringe 2 is inserted therein. The tubular cover 2.4 can be easily grasped and pulled in the proximal direction P, and the needle cap 2.1 can be removed from the proximal tip of the filled syringe 2.

  Alternatively, the needle cap 2.1 and the tubular cover 24 can be arranged integrally.

  4A and 4B show the front device 1 connected to the rear device 3. The tubular cover 2.4 and the needle cap 2.1 are removed from the filled syringe 2 held in the front device 1, and the injection needle 2.1 is exposed. The front device 1 is attached to the rear device 3 by a latch arm 1.1.2 that latches at the proximal end of the housing 3.1 of the rear device 3.

  Grasp mounting sleeve 1.11 and axially displace mounting sleeve 1.11 against outer sleeve 1.1 in the proximal direction P to the unlocked position against the biasing force of mounting sleeve spring 1.7. As a result, the front device 1 is attached to or removed from the rear device 3. With the mounting sleeve 1.11 in the unlocked position, the tubular end of the housing 3.1 is pressed against the slope of the latch arm 1.1.2 during insertion or removal, thereby causing the latch arm 1. 1.2 can be deflected radially outward. This allows the tubular end of the housing 3.1 to be inserted into and / or removed from the open distal end of the front device 1 when the mounting sleeve 1.11 is in the unlocked position. Can do. When the tubular end is fully inserted, the latch arm 1.1.2 can be loosened and latched into each opening of the tubular end of the housing 3.1.

  When the rear device 3 is attached to the front device 1, the user can release the attachment sleeve 1.11 so that the attachment sleeve spring 1.7.1 moves the attachment sleeve 1.11 into the locked position. Can be translated. When the tubular end of the housing 3.1 is inserted into the open distal end of the front device 1, the plunger 3.2 is inserted into the outer cylinder 2.3 so as to engage the stopper 3.3 of the syringe 2. Is done. The latch arm 1.1.2 latches at the proximal end of the housing 3.1 and attaches the front device 1 to the rear device 3. When releasing, the mounting sleeve 1.11 is driven back to the locked position L by the mounting sleeve spring 1.7.1. The mounting sleeve 1.11 in the locking position L abuts the latch arm 1.1.2, and the latch arm 1.1.2 prevents deflection outward in the radial direction so that the proximal end of the housing 3.1 Is disengaged from the front device 1. Auto-injector A is assembled and ready to be used for injection to administer a dose of drug to the patient.

  As the needle shroud 1.4 is pressed against the skin of the patient receiving the injection, the needle shield 1.4 is translated into the outer sleeve 1.1 to the retracted position PR. As best seen in FIG. 4B, the extension arm 1.4.2 engages the release bevel 1.3.3 to deflect the flexible arm 1.3.2 radially inward, The syringe holder 1.3 is released from the outer sleeve 1.1 and translates in the proximal direction P. The reusable motor 3.5 of the rear device 3 can be activated to translate the syringe holder 1.3 and the filled syringe 2 in the proximal direction P.

  The needle shroud 1.4 has the function of telling the posterior device 3 that the needle shroud 1.4 is in contact with the patient's skin. The rear device 3 can include a mechanism such as an interlocking switch that can release the dose of the drug contained in the syringe 2 only when the contact of the needle shroud 1.4 with the skin is detected.

  5A and 5B are two cross-sectional views during injection of the anterior device 1 attached to the posterior device 3. The syringe holder 1.3 that holds the syringe 2 moves proximally to the second position II where the return spring 1.8 is compressed. The injection needle 2.2 protrudes in the proximal direction P from the front device 1 and is inserted into the patient's skin. The injection depth can be defined by the length of the compressed return spring 1.8 between the rib 1.1.1 and the syringe holder 1.3. Alternatively, the needle shroud 1.4 can include stops or ribs (not shown) that interact with the syringe holder 1.3 to limit the puncture depth of the injection needle 2.2.

  When the syringe holder 1.3 is lowest, the plunger 3.3 connected to the stopper 3.3 is driven in the proximal direction P by the motor 3.5 of the rear device 3, and the dose of the medicine contained in the syringe 2 is reached. Is released through the needle 2.2.

  After the dose of drug has been delivered, the auto-injector A can be removed from the injection site and the needle shroud 1.4 can be advanced to the advanced position PA driven by the transmission spring 1.5. Since this movement can be detected by the rear device 3, the syringe 2 can be retracted by releasing the plunger 3.2 or actively pulling it out. The syringe holder 1.3 is returned to the first position I by the action of the loose return spring 1.8, whereby the injection needle 2.2 is withdrawn from the patient's skin and within the needle shroud 1.4. Covered with needles to prevent access to the needle.

  Alternatively, or in addition, the direction of the motor 3.5 is reversed and the syringe 2 and the syringe holder 1.3 are retracted to the first position I.

  When the transmission spring 1.5 is loosened and the needle shroud 1.4 is returned to the advanced position PA, the extension arm 1.4.2 disengages the release ramp 1.3.3. When the syringe holder 1.3 returns to the first position I, the flexible arm 1.3.2 latches on the outer sleeve 1.1 and the syringe holder 1.3 again on the outer sleeve 1.1. Install. The auto-injector A is disassembled and the rear device 3 is removed from the front device 1. For this purpose, the mounting sleeve 1.11 is gripped and axially displaced in the proximal direction P to the unlocked position against the outer sleeve 1.1 against the biasing force of the mounting sleeve spring 1.7. With the mounting sleeve 1.11 in the unlocked position, the tubular end of the housing 3.1 presses against the ramp of the latch arm 1.1.2 when pulled away from the reusable front end 1 As a result, the latch arm 1.1.2 can be deflected radially outward. The tubular end of the housing 3.1 can be removed from the open distal end of the front device 1 when the mounting collar 1.11 is in the unlocked position. When the tubular end is removed, the latch arm 1.1.2 can be loosened. The mounting sleeve 1.11 returns to the locked position when released. Since the tubular cover 2.4 holding the needle cap 2.1 is reinserted at the open proximal end of the front device 1, the injection needle 2.2 is covered by the needle cap 2.1. Tubular cover 2.4 is pushed into front device 1 to remove syringe 2 from syringe holder 1.3. Thereafter, the empty syringe 2 can be removed from the front device 1 and placed. Alternatively, the entire front device 1 can be discarded to reduce the risk of cross-contamination.

  6A and 6B are a perspective view and a cross-sectional view of the assembled auto-injector A with the rear device 3 and the front device 1. The rear device 3 and the front device 1 comprise a compression sleeve comprising a mounting sleeve 1.1, a mounting sleeve spring 1.7.1, and a latch arm 1.1.2 that engages the proximal end of the housing 3.1. Attached to each other by means.

  The housing 3.1 of the rear device 3 has a substantially elliptical cross section of different sizes.

  The reusable rear device 3 of the auto-injector A inserts and / or retracts the injection needle 2.2 by actuating and stopping an electric motor 3.5 that translates the plunger 3.2 in the axial direction. A plurality of control elements 3.6 used to activate and control various functions of the auto-injector A, such as injecting various doses. Furthermore, the needle insertion speed or the puncture depth of the injection needle 2.2 can be controlled and / or a time delay can be introduced by the user. The posterior device 3 can comprise various user-selectable speed profiles that control the torque provided by the motor to facilitate the needle insertion process and / or modify the injection speed. Various parameters can be modified to meet drug requirements such as user and / or drug viscosity.

  The rear device 3 can comprise a memory unit (not shown) that can be used to store user related data for compliance monitoring. If the patient is on medication, the posterior device 3 can be used to monitor that drug doses are being administered at the correct regular intervals. In addition, a set of device specification parameters can be stored in the memory unit. The specification parameters can be compared to the actual parameters determined during use of the automatic injector A. For example, the force required to insert the injection needle 2.2 into the skin is characterized by the current measured during the needle insertion process. If the measured current is out of specification, the rear device 3 can detect misuse of the automatic injector A and stop the injection. Another possible application involves comparing the initial position of the stopper 3.3 with the corresponding specification parameters at the start of the injection. If the position of the stopper 2.5 is out of specification, the rear device 3 detects that a used empty syringe 2 is loaded into the front device 1 and disables the injection mechanism to prevent damage. it can. The automatic injector A cannot operate when the syringe 2 is not inserted into the syringe holder 1.3.

  The posterior device 3 can have a display 3.7, preferably a liquid crystal display (LCD), which can visually display drug properties such as injection progress, injection completion, historical user data and / or expiration date. . The display 3.7 can display a message reminding the patient to administer the medication, specification parameters, operating modes, and / or the type of medication contained in the filled syringe 2. In addition or alternatively, the posterior device 3 may comprise suitable means for providing audio and / or tactile feedback to the patient and / or the user of the auto-injector A.

  The rear device 3 may comprise a sensor unit (not shown) capable of detecting actual parameters such as the type of drug or drug contained in the prefilled syringe 2, in particular by means of wireless automatic identification (RFID) or barcode reading. . This allows automatic configuration of the automatic injector A for drug properties. For example, the puncture depth of the injection needle 2.2 can be automatically adjusted to the depth required by the medicine. Automatic syringe A is particularly adapted for use in the administration of various drugs that may be required for intradermal, transdermal or intramuscular injection.

  Further sensor units (not shown) can be arranged in particular as microswitches that detect the correct assembly of the auto-injector A and / or the correct attachment of the front device 1 to the rear device 3. The sensor unit can also be arranged as an encoder, light gate, and / or current monitoring system.

  The motor 3.5 of the auto-injector A is powered by an energy supply 3.8 that can be performed by a rechargeable or disposable battery set. Torque provided by the motor 3.5 can be transmitted to the plunger 3.2 by a gear box 3.9 including a plurality of gears 3.9.1 and a worm gear 3.9.2. A plurality of gear teeth 3.2.1 with which one of the gears 3.9.1 is engaged is formed on the plunger 3.2 so that the rotational movement of the plunger 3.2 is like a rack and pinion gear pair. It can be converted to linear motion. The gearbox 3.9 specifically increases the output torque delivered to the plunger 3.2 to deliver the necessary plunger motion and force.

  An alternative rear device 3 can be arranged without a gearbox. Other forms of gearbox are equally applicable, for example lead screws driven directly or indirectly by a motor.

  The distal displacement of the interlock shroud connected to the needle shroud 1.4 can be detected by the interlock switch 3.10. The detected distal position PA, PR of the needle shroud 1.4 indicates whether the auto-injector A is correctly placed on the patient's skin so that a dose of the drug can be injected. The posterior device 3 can be programmed so that the motor 3.5 can only be activated when the needle shroud 1.4 is in contact with the patient's skin. Furthermore, the direction of the motor 3.5 can be reversed immediately when the automatic injector A is removed from the injection site at any point in the injection to allow partial delivery of the drug dose. When the automatic injector A is removed from the injection site, the needle 2.2 is retracted to reduce the risk of needle stick accidents. Removal from the injection site can be detected by returning the needle shroud 1.4 to the advanced position PA.

  The electronic control unit 3.11 can be arranged in the rear device 3, and in particular in the housing 3.1 which controls the various functions of the motor 3.5. The electronic control unit 3.11 can comprise a printed circuit board (PCB). A closed loop motion control device that controls the speed of the motor 3.5 is embedded in the electronic control unit 3.11 to reduce the impact load on the reusable auto-injector A and / or the syringe 2 so Risk can be reduced.

  The electronic control unit 3.11 can detect the stall of the motor 3.5 at the end of the injection stroke that delivers the dose of drug to the patient. This indicates that the syringe 2 is completely empty and the needle retraction mechanism of the automatic injector A can be activated.

  An encoder sensor 3.12 capable of determining the position of the plunger 3.2 is connected to the gearbox 3.9. The detection of the position of the plunger 3.2 is used to achieve a gradual movement of the plunger during injection. This allows the translational speed of the plunger 3.2 to be adjusted to various stages of drug delivery including the needle insertion stage, drug release stage, and needle retraction stage. Needle insertion is considered to be less painful to the patient when performed quickly, whereas injection is considered less painful when performed more slowly.

  Although the rear device 3 of the embodiment described above is motor driven, the front device 1 described above can likewise be combined with a rear device having different propulsion means such as compression springs, torsion springs, gas springs or combustion engines. .

  The rear device 3 described above can likewise be combined with a disposable front device that is completely discarded after use. Although the reusable front device 1 requires less resources and requires less waste, the disposable front device avoids the risk of cross-contamination because there are no parts that contact multiple patients.

1 Front device 1.1 Outer sleeve 1.1.1 Annular projection 1.1.2 Latch arm 1.1.3 First recess 1.1.4 Second recess 1.3 Syringe holder 3.2 Flexible arm 1.3.3 Release slope 1.3.4 First fastener 1.3.5 Abutment surface 1.3.6 Holding projection 1.3.7 Friction rib 1.4 Needle Shroud 1.4.2 Extension arm 1.4.2.1 Interlocking shroud 1.4.3 Annular flange 1.4.4 Second fastener 1.5 Transmission spring 1.7.1 Mounting sleeve spring 1.8 Return spring 1.11 Mounting sleeve 2 Syringe 2.1 Needle cap 2.2 Injection needle 2.3 Outer cylinder 2.3.1 Outer cylinder collar 2.4 Tubular cover 3 Rear device 3.1 Housing 3.2 Plunger 2.1 Gear teeth 3.3 Stopper 3.4 Third orifice .5 Motor 3.6 Control element 3.7 Display 3.8 Energy supply 3.9 Electronic components 3.9.1 Gear 3.9.2 Worm gear 3.10 Interlocking switch 3.11 Electronic control unit 3.12. Encoder / Sensor A Auto-injector X-axis PR Retraction position PA Advance position I First position II Second position L Lock position P Proximal direction D Distal direction

Claims (5)

A front part device (1) and and a reusable rear devices (3), automatic injector for administering a dose of liquid medicament (A),
The front device (1) is configured to receive a syringe (2) comprising an injection needle (2.2) and an outer cylinder (2.3) containing a dose of drug;
A tubular outer sleeve (1.1);
A compression coupling means for attaching the front device (1) to the rear device (3) of the auto-injector (A);
With
A syringe holder (1.3) configured to receive a prefilled syringe (2) is slidable relative to the outer sleeve (1.1) and the injection needle (2.2) is external Between a first position (I) hidden in the sleeve (1.1) and a second position (II) where the injection needle (2.2) projects proximally from the outer sleeve (1.1) Arranged to translate, the syringe holder (1.3) can be hooked to the outer sleeve (1.1) to release the syringe holder (1.3) to the first position (I) Comprising at least one flexible arm (1.3.2) arranged to hold;
Here, the compression connecting means is
An annular mounting sleeve (1.11) that is axially displaceable parallel to the longitudinal axis (X) between the locked position (L) and the unlocked position;
A mounting sleeve spring (1.7. 1) biasing the mounting sleeve (1.11) towards the locking position (L);
Comprising at least one latch arm (1.1.2) connected to the rear device (3),
The latch arm (1.1.2) is radially deflectable and the mounting sleeve (1.11) in the locked position (L) is the radial deflection of the latch arm (1.1.2). The mounting sleeve (1.11) in an unlocked position, arranged to prevent the latching arm (1.1.2) from being assembled to the rear device (3) of the front device (1), or Latching to deflect by disassembly from the rear device (3) and allow latching to the rear device (3) of the front device (1) or unlatching from the rear device (3)
Allowing radial deflection of the arm (1.1.2),
The reusable rear device (3)
The housing (3.1),
A plunger (3.2) connected or configured to engage a stopper (3.3) that provides a fluid tight seal against the distal end of the outer tube (2.3);
A motor (3.5 ) for displacing the plunger (3.2) connected to the stopper (3.3 )
With
Front device (1) is Ri can der attached to the rear device (3) via said compression coupling means,
The rear device (3) includes a sensor unit for detecting actual parameters of injection, a memory unit for storing user related data and / or specification parameters, and a user of the automatic injector (A). Providing means for providing visual, auditory and / or tactile feedback,
Further, the sensor unit detects the initial position of the stopper (3.3), and if the stopper is outside the standard of the predetermined specification parameter, the rear device (3) Detecting that it is loaded and invalidating the injection,
An automatic syringe (A) characterized by the above . A needle shroud (1.4) configured to rest on the patient's skin is slidably disposed relative to the outer sleeve (1.1), and the needle shroud (1.4) is in an advanced position. Arranged to translate between (PA) and retracted position (PR) and engages release ramp (1.3.3) on syringe holder (1.3) in retracted position (PR) And an extension arm (1.4.2) arranged to unlatch the syringe holder (1.3) from the outer sleeve (1.1). Automatic syringe (A) . The tubular cover (2.4) is connected to a needle cap (2.1) that covers the injection needle (2.2) of the syringe (2), and the tubular cover (2.4) is connected to the front of the syringe (2). when held in the device (1), characterized in that it is positioned so as to facilitate removal of the needle cap (2.1), automatic injector according to claim 1 (a). The interlock switch (3.10) is arranged to detect the position (PA, PR) of the needle shroud (1.4),
The automatic injector (A) according to claim 2 . The automatic device according to any one of claims 1 to 4 , characterized in that the rear device (3) further comprises an encoder sensor (3.12) capable of determining the position of the plunger (3.2). Syringe (A).

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